1. Field of the Invention
The present invention relates to a radiographic apparatus that acquires radiographic images when exposed to radioactive rays.
2. Description of the Related Art
An x-ray radiography system, an example of radiography systems, includes an x-ray projector for projecting x-rays toward a subject and a radiographic apparatus for acquiring x-ray images of the subject from the x-rays having been projected from the x-ray projector and penetrating through the subject. The x-ray projector includes an x-ray source, a radiation source controller, and an activation switch for inputting an x-ray radiation start signal. The radiographic apparatus includes an x-ray image detector for detecting a radiographic image or x-ray image from the x-rays having been penetrating through the subject, and an imaging controller for controlling operation of the x-ray image detector.
An x-ray image detector using a flat panel detector (FPD) in place of conventional x-ray film or imaging plates (IP) has recently been widely spread. The FPD has a large number of pixels arranged in a matrix, to accumulate signal charges corresponding to incident amounts of x-rays on the respective pixels. The FPD converts the signal charges accumulated in the respective pixels to a voltage signal through a signal processing circuit, to detect an x-ray image representative of graphic information on the subject, and output the detected x-ray image as digital image data.
Portable x-ray image detectors, called electronic cassettes, have also been used in practice, which contains a flat panel detector in a rectangular box-shaped body. The plane size of the electronic cassette 21 is about the same as those of radiographic film cassettes and IP cassettes. The electronic cassette can be mounted in a conventional radiographic stand or table which is adapted to the film cassette or IP cassette. In addition, the electronic cassette can be used independently. For example, in order to image such a site of a test subject that is hard to image using the electronic cassette as mounted in the stationary radiographic stand or table, the electronic cassette may be put on a bed with the test subject or may be held directly by the test subject. Moreover, the electronic cassette may be carried around for use in home medical care or emergency medical care at accident sites or disaster sites.
The electronic cassettes include wired types and wireless types. The wired type electronic cassette is connected to a cable for signal transmission from and to the imaging controller or for power-supply from a power source, as disclosed for example in U.S. Patent Application Publication No. 2004/0114725 corresponding to (JPA 2004-173907) and JPA 2010-115390. In U.S. Patent Application Publication No. 2004/0114725, an imaging controller (system control section) and a power supply are integrated into a unit, and a composite cable connected to the electronic cassette is connected through a connector to another composite cable that is connected to the imaging controller and the power supply. The first prior art also discloses an embodiment, in which a battery for power-supply is built in the cassette, and a wireless module for wireless communication is attached to a composite cable that is connected to the cassette.
The second prior art discloses a radiographic cassette holding device, a radiographic stand or table, for mounting the electronic cassette during the radiography. The radiographic cassette holding device is provided with a connector that may be connected to a socket or connector of the electronic cassette through a direct contact or the like, to supply the electronic cassette with power from an external commercial power source. Through this connector, the electronic cassette may also exchange data with the imaging controller.
In a hospital having multiple radiography studios, each studio is usually installed with complete system components so that imaging with the electronic cassette may be executed in parallel in any studio. In that case, the electronic cassette may be moved from one studio to another. If the cable to be connected to the electronic cassette should also be moved across the studios along with the cassette, the cable could tangle in other medical equipment. To avoid such inconvenience, at least one cable is fixedly installed in each studio in the practice, so that it is only necessary to carry about the electronic cassette and connect it to the stationary cable to use it in each studio.
As described in the first prior art, the composite cable for the electronic cassette consists of a couple of cables which are respectively connected to the imaging controller and the power supply. In one conventional example, these cables are bundled together into a composite cable at an output point proximate to the imaging controller and the power supply. Alternatively, where the imaging controller and the power supply are built in a unit, cables from the imaging controller and the power supply are bundled into a composite cable inside the unit housing, and the composite cable is extended from the housing.
The imaging controller and the power supply are conventionally installed in every radiographic studio. This is because at least a power supply unit is necessary in each studio to carry out the imaging with the electronic cassette in parallel or simultaneously in the multiple radiography studios. Since the imaging controller is conventionally coupled to the power supply unit through the bundling of their cables into one composite cable, the imaging controller has also been installed in every radiographic studio. It may be possible to branch the composite cable into two cables at a point proximate to the power supply unit and elongate the cable to the imaging controller so as to share one imaging controller with multiple studios while installing the power supply unit in each radiographic studio.
However, the elongated cables from the respective studios to the shared imaging controller would complicate the wiring across the studios or could hinder the radiographic operation, for example, by getting tangled with the leg of the radiologist or the patient. The same problem could occur in the above mentioned prior art systems. Installing multiple imaging controllers aside from multiple power supply units, however, requires greater space and higher cost.